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arXiv · 2004.07540

On angles, projections and iterations

Christian Bargetz·Jona Klemenc·Simeon Reich·Natalia Skorokhod
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Abstract

We investigate connections between the geometry of linear subspaces and the convergence of the alternating projection method for linear projections. The aim of this article is twofold: in the first part, we show that even in Euclidean spaces the convergence of the alternating method is not determined by the principal angles between the subspaces involved. In the second part, we investigate the properties of the Oppenheim angle between two linear projections. We discuss, in particular, the question of existence and uniqueness of "consistency projections" in this context.

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Christian Bargetz, Jona Klemenc, Simeon Reich, Natalia Skorokhod. 2020-04-16. On angles, projections and iterations. https://doi.org/10.1016/j.laa.2020.05.023

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